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关键词： 多天线通信系统   射频标签   高维空间聚类   二阶非圆信号   宽线性处理   最小均方误差   信干噪比   逐次干扰消除   非正交接入  

摘要： 近些年,基于反向散射理论的超高频射频识别标签（RFID）技术发展迅速,已经逐渐应用到生产生活中的各个领域。RFID技术在智能交通、智能物流、公共安全等领域的应用给物流行业、制造行业、仓储行业、服装行业、医疗行业、图书行业、农牧行业等各行各业带来了极大的便利,使人们的生产生活更加便捷。此外,RFID技术在零售业、智慧城市、国防军事等领域的应用也越来越普遍,它已成为国家未来物联网系统的重要组成部分。尽管RFID技术在不断拓展其应用领域,适用范围也越来越广泛,然而当前的超高频反向散射RFID系统仍然存在标签访问距离短,访问效率低等问题,从而制约了RFID技术的进一步发展。这其中除了系统发射功率受限,反向散射通信信道衰落大,标签激活功率阈值高的问题外,一个主要原因是当前的RFID系统都采用了单天线通道的通信系统。由于多天线MIMO系统可以通过在通信系统收发端增加多个发射或接收通道来增强通信链路的吞吐量和可靠性,因此相关领域内的研究人员近年来也开始关注多天线RFID系统的设计与性能分析。目前在5GHz频段,多天线RFID系统的研究取得了一定成果。但在超高频（800MHz～900MHz）频段,关于如何有效地将多天线技术应用到RFID系统中的问题,目前还没有太多有价值的研究成果。有鉴于此,本论文对多天线技术在超高频RFID系统中的应用进行了深入研究,提出了适应于超高频RFID系统的信号处理算法,并深入研究了这些算法的性能,实现了应用和理论的创新。本论文的研究工作主要包括以下几个方面:提出了一种适用于多天线超高频反向散射系统的高维空间标签数量估计方法。该方法适应于RFID系统只需要获知其访问范围内物品的数量而不需要访问物品详细信息的场景。与常见的多天线选择算法或是最大合并比算法不同,该方法既充分利用了多个天线接收到的不同路径信号的信息,又避免了类似最大合并比算法中所需的信道估计步骤,因而其不仅具有实现复杂性低,而且可以在很短时间内估计出当前系统访问的标签的数量。仿真和实物验证证明,在低信噪比情况下,该方法估计性能优于现有方法,在实际中具有很好的应用前景。提出了一种基于宽线性最小均方误差准则的标签“防冲突”算法。该方法利用超高频反向散射系统中标签的反射信号是非圆信号的特点,采用宽线性信号处理技术充分地挖掘了标签信号中包含的二阶非圆统计信息,提高了系统对标签“冲突”信号的检测能力,降低了标签“冲突”现象对系统吞吐量的影响。数值仿真结果和实物验证结果表明,在超高频反向散射系统中采用宽线性检测器能取得比传统线性检测器的更优越的性能,该检测器在多天线超高频反向散射系统中的应用取得了满意的效果。提出了一种基于非正交接入理论的多天线超高频反向散射系统（NOMA-RFID）,并且在理论上证明了NOMA-RFID系统的信道容量大于时分多址接入的RFID系统,并且在系统信道容量最大和标签接入公平性最大两种场景下,给出了NOMA-RFID系统的功率分配方案;考虑到前两种功率分配方案对不同场景不具有自适应性,本文进一步给出了一种基于标签数量的功率分配算法,该算法根据不同标签簇内未访问标签的数量自适应地进行功率分配,可以适应于不同的标签访问场景,在标签接入的公平性和系统总容量之间取得了很好的折中;此外,本文给出了非圆信号下NOMA-RFID系统的信道容量表达式,讨论了信号非圆特性对NOMA-RFID系统总容量的影响,在理论上证明了当NOMA-RFID系统存在误码传播时,采用非圆信号后的NOMA-RFID系统容量要大于采用圆信号的NOMA-RFID系统容量,并提出了一种基于可调非圆系数的系统容量分配方案,揭示了非圆信号在NOMA-RFID系统中的应用潜力,最后,本文分析了一种基于WLMMSE-SIC检测器的NOMA-RFID系统的性能,给出了标签信号SINR的分布函数、中断概率和误码率的闭合表达式。分析了任意天线配置下的宽线性最小均方误差（WLMMSE）检测器输出信号的信干噪比（SINR）的分布特性以及基于WLMMSE检测器的MIMO通信系统的性能。证明了包含N_t个发送天线和Nr个接收天线的WLMMSE MIMO通信系统检测器信号的SINR分布等价于N_t个具有不同参数的Gamma随机变量的和的分布,并给出了任意天线配置下检测信号的SINR分布函数的近似闭合解析表达式。该表达式简洁明了,并且该表达式给出的理论结果与仿真结果吻合的非常好。仿真结果显示该表达式不仅适用于小规模MIMO系统的性能分析,也适应于大规模MIMO系统性能的分析。此外,本文还利用WLMMSE检测器SINR的分布表达式,分析了任意天线配置下的WLMMSE MIMO系统的性能,所得到的结果不仅很好的解释了宽线性防冲突算法的仿真结果和实验现象,并且为其他基于宽线性处理技术的MIMO通信系统的性能分析提供了

关键词： RFID   IoT and SCM  

摘要： Supply Chain Management (SCM) is increasingly complex and dynamic. Radio frequency identification (RFID) and the Internet of Things (IoT) are expected to play a significant role in fulfilling customer requirements in the supply chain. In this work, the integration of RFID with IoT is called RFID-IoT. RFID-IoT strives to develop automated sensing, seamless, interoperable and highly secure systems by connecting IoT devices through the internet. In this paper, the authors have systematically reviewed the selected literature on the application of RFID-IoT in supply chain management. The contribution of this paper is to review the current state-of-the-art literature and potential trend on the application of RFID-IoT in SCM. There is a need for an in-depth, comprehensive analysis of up-to-date literature to help enhance the management system efficiency, maximize productivity, and minimize cost. This work also explores the current challenges of the reviewed papers in RFID-IoT implementation in the supply chain. The conceptual framework model has been conducted from four major critical SCM perspectives: product manufacturing, shipping and distribution, inventory and retail shop. In the future, this review's highlighted insights and recommendations will hopefully lead to increased efforts toward developing RFID-IoT technologies.

关键词： Defected microstrip surface   impedance matching   metal mountable tag antenna   miniature UHF tag antenna  

摘要： This study presents a novel miniature ultra-high frequency (UHF) radio frequency identification (RFID) tag for metallic objects. Its arrangement includes a U-shaped feeder, which is inductively coupled to two E-type connected patches. Size reduction is achieved by means of utilizing the U-shaped feeder, and introducing a defection in the connection between the two E-type patches. The defection in the connection area between the patches modifies the current distribution by increasing the electrical length, and the antenna inductance. Furthermore, increasing the length of the U-shaped structure significantly raises the antenna inductance and, consequently, the flexibility of the structure for the impedance matching purpose. Polytetrafluoroethylene (PTFE) is employed for the fabrication of the designed tag. The tag's size is 65 mm x 20 mm x 1.5 mm, and does not require any complex fabrication process such as utilization of metal vias and/or shorting stubs. It is observed that with 4W EIRP, the measured detection distance is 6.9 m when it is attached onto metal sheets (20 cm x 20 cm), and 5.54 m when it is in free space. The measurement results also are in good agreement with the simulated results.

关键词： Data acquisition  

摘要： Aiming at the problems of slow drug data acquisition speed and large detection error in the existing drug quality detection methods, a fast drug quality detection method based on RFID technology is proposed. Firstly, the drug quality data is extracted through the reading function in RFID technology. Then, setup the drug quality dataset and determine the data characteristics remove the noise in the data with the help of unsupervised feature selection algorithm. Finally, determine the similarity of drug quality, and calculate the contribution weight of the data with the help of telescopic moving window. The model of drug quality detection is constructed by Bayesian algorithm to complete the detection. The experimental results show that the drug quality data obtained by RFID technology is fast, and the drug quality detection error is small. Copyright © 2022 Inderscience Enterprises Ltd.

关键词： Cybersecurity   Physical access control   RFID   RFID access control   RFID authentication system  

摘要： The problem addressed in this study is the lack of clearly defined methods cybersecurity professionals can use to reduce threats against existing radio frequency identification (RFID) authentication systems. This research focused on low frequency (LF) RFID authentication system operating at the 125 kHz frequency. Although updated technology such as near field communication (NFC) systems could be implemented to address common security concerns with existing RFID authentication systems, not all organizations have the option of upgrading. Therefore, a panel of cybersecurity experts was asked to provide innovative solutions to help address the research problem to address security concerns around existing RFID authentication systems. The purpose of this qualitative Delphi study was to collect the opinions from a panel of cybersecurity experts to determine innovative ways security can be added to existing RFID authentication systems. The study was conducted using a panel of 13 penetration testers within the field of cybersecurity using three rounds of questionnaires. The first round of questions was to determine what issues affected RFID authentication systems. The second round was to gather innovative ideas from the panel of experts on how to address the identified problems. Finally, the third round was used to rank the likelihood that each of the proposed solutions would be accepted by the end-users and therefore help increase the security of the RFID authentication system. The results from the study provided three possible solutions to add security to an existing RFID authentication system. The solutions included adding a pressure-sensitive button to an RFID tag, adding a signal blocking cage around the RFID readers, and adding information to a security awareness training program on the importance of the RFID authentication system. Each of these proposed solutions can be used to increase the security of an existing RFID authentication system in various ways.

关键词： 石油工具   库房管理系统   人脸识别   射频识别   预警机制  

摘要： 近年来，国内油气资源对外依存度不断升高，国际国内形势剧烈变化，国家在油气行业实施“七年行动计划”，海洋石油行业迎来快速发展阶段，使用的石油工具种类和数量大幅增多，给石油工具的精细管理带来巨大压力。传统石油工具管理方式具有工具编码识别困难、管理信息化水平低、信息安全性不足、数据挖掘能力不足的问题，亟需进行数字化转型。基于此，本文设计实现了面向物与人的石油工具库房管理系统，用以解决库房管理中的痛点问题，本文的主要工作如下:　　(1)本文针对当前石油工具管理情况开展调研，分析库房管理中的痛点，根据业务场景对人员管理、工具管理和关键功能需求进行分析，在模型-视图-控制器三层架构的基础上设计七层架构的库房管理系统，并给了各层的详细功能。　　(2)为提高系统安全性，防止数据被窃取，设计实现了人脸识别登录模块，该模块采用多任务卷积神经网络算法进行人脸检测，十八层卷积神经网络进行人脸识别，大幅度提高了非授权用户进入系统的难度;为解决工具编码识别困难的问题，对射频标签和阅读器进行了优化选型，并针对石油工具的特性优化了标签处理工艺;为提高数据分析挖掘能力，采用K均值聚类算法与统计方法，结合现场实际设计实现预警模块。　　(3)本文对系统关键模块人脸识别、射频识别和预警功能以及管理功能根据黑盒方法进行了功能测试与展示，系统功能与性能符合预期。　　本文采用射频识别和人脸识别技术，设计实现了面向物与人的石油工具库房管理系统，有效提升了石油工具的信息化管理水平，提高了工作效率与安全性，通过预警机制实现管理数据价值输出，辅助管理人员进行科学决策，可以有效解决石油工具库房管理中的痛点问题。

关键词： Competition  

摘要： As an important part of modern logistics, warehousing provides a guarantee for the sustainable stability of enterprises, so as to realize the economy of enterprise production and transportation and so as to realize the economy of enterprise production and transportation. With the advent of the information age, the traditional logistics management model has been difficult to adapt to the current increasingly fierce market competition environment. In the management of cross-border e-commerce enterprises, warehouse management must establish a systematic and information-based logistics warehouse management system to improve the level of logistics management. Passive wireless RFID asset management provides a new idea for the construction of warehousing management system of cross-border e-commerce enterprises. Through the application of RFID technology, the warehousing design scheme and process of cross-border e-commerce enterprises can be optimized and controlled to the greatest extent, so as to strengthen the optimization and integration of supply chain and improve the market competitiveness of logistics enterprises. Based on the wireless passive RFID asset management technology, this paper analyses the construction and optimization of the logistics warehouse management system of cross-border e-commerce enterprises. The simulation results show that after the application of wireless passive RFID asset management technology, the warehouse operation efficiency of cross-border e-commerce enterprises is improved, the employee utilization rate is relatively reduced, and at the same time, it can also save a lot of manpower and reduce the labour cost.

摘要： In this paper, the authenticity of news information on the 5G Internet of Things (IoT) is studied, and a network false news information screening platform is designed and optimized by IoT combined with passive RFID. The electronic license chain based on data sovereignty is established, in which, combined with the identity identification and strong correlation ability based on the electronic license chain, a cross-industry, cross-business, and cross-field behavior record base database is formed;then, a digital library is constructed based on this base library;finally, through data sharing and management, a false news information feature extraction and screening platform is formed for the orderly management and reasonable dispatch of government resources and reducing various risks. The main functional modules implemented by the platform are the acquisition of news data and comment data, the retrieval and analysis of news data, the false detection of online news, and the visualization of false news data. However, there is still much public who are not aware or do not understand that news truth is this dynamic form. Therefore, this paper aims to inform the public that news truth in news context is a dynamic process by 5G Internet of Things combined with passive RFID. The public understands the circumstances where news truth may be dynamic truth to avoid being misled by false news.

关键词： Protocols   Authentication   Radiofrequency identification   Privacy   Servers   Computer science   Internet of Things   Active tags   authentication   privacy   radio-frequency identification   RFID   security   zero-knowledge  

摘要： An RFID system is a contactless automatic identification technology and a solution to many business and personal applications. However, the privacy threats to RFID systems cause significant concerns in real RFID applications. Among the privacy issues in RFID systems, we are particularly interested in designing an RFID authentication protocol that achieves strong indistinguishability-based privacy (ind-privacy) and possesses the zero-knowledge property for active tags. In this article, a zero-knowledge authentication protocol (ZKAP) using quadratic residues is proposed. Then, an indistinguishability-based experiment using random oracles is modeled to prove that the proposed scheme achieves strong ind-privacy against active eavesdroppers. The zero-knowledge property is defined with respect to the tags' private information against dishonest readers, and that property of our ZKAP is proven by constructing a polynomial time simulator that generates a transcript with the same distribution as that of ZKAP. Finally, the proposed protocol is implemented in a Raspberry Pi and a PC, and the performance is evaluated in terms of authentication time. The experimental results demonstrate that our ZKAP achieves its design goals.

关键词： Supply chain management  

摘要： This paper proposes a new tag anticollision algorithm. On the basis of the common query tree algorithm, this algorithm increases the number of query bits, so that the algorithm has a faster tag identification amount in the state of full time slots. Collision bit and total response bit are used to estimate the number of tags, and combined with the highest collision bit to determine whether it is continuous, the number of query crosses is adaptively adjusted, and a variable bit dynamic query tree tag anticollision algorithm is designed. In conjunction with the settlement environment, improvements have also been made in the status of the identified tags. The new algorithm has improved progress in reducing idle time slots and reducing search depth. Under the premise of ensuring stability, the recognition efficiency of the algorithm is improved. From the perspective of different dimensions of corporate network and marketing dynamic capabilities, based on the strength of network relationships and product development processes, it can promote value creation model innovation in business model innovation. That is, when the network partners communicate very frequently, they can provide new ideas and resources for enterprise product development and creation and then can better integrate innovation through product innovation, quality improvement, product development cycle shortening, and development advance management. Typed products and resources are put into the operation process of the industrial chain of product output to better create new products for customers and lay the foundation for realizing the innovation of corporate value creation models. Based on the network density and customer relationship process, it can promote the value proposition model innovation in the business model innovation. Enterprise business model innovation should not only pay attention to the collaborative innovation between different elements within the enterprise but also pay attention to the o